Fix a cpufreq userspace limitation bug

Fix a cpufreq userspace limitation bug, so that userspace freq can
return to correct freq when freq_limitation return to high value (like
ppc event)

Signed-off-by: Liu, Jinsong <jinsong.liu@intel.com>=

1 files changed, 38 insertions, 11 deletions

diff --git a/xen/drivers/cpufreq/cpufreq_misc_governors.c b/xen/drivers/cpufreq/cpufreq_misc_governors.c
index a375a25bb9..1c63ec1815 100644
--- a/xen/drivers/cpufreq/cpufreq_misc_governors.c
+++ b/xen/drivers/cpufreq/cpufreq_misc_governors.c
@@ -18,34 +18,38 @@
 #include <xen/sched.h>
 #include <acpi/cpufreq/cpufreq.h>
 
-static unsigned int usr_speed;
-
 /*
  * cpufreq userspace governor
  */
+static unsigned int cpu_set_freq[NR_CPUS];
+
 static int cpufreq_governor_userspace(struct cpufreq_policy *policy,
                                       unsigned int event)
 {
     int ret = 0;
-    unsigned int freq;
+    unsigned int cpu;
 
-    if (!policy)
+    if (unlikely(!policy) || 
+        unlikely(!cpu_online(cpu = policy->cpu)))
         return -EINVAL;
 
     switch (event) {
     case CPUFREQ_GOV_START:
+        if (!cpu_set_freq[cpu])
+            cpu_set_freq[cpu] = policy->cur;
+        break;
     case CPUFREQ_GOV_STOP:
+        cpu_set_freq[cpu] = 0;
         break;
     case CPUFREQ_GOV_LIMITS:
-        freq = usr_speed ? : policy->cur;
-        if (policy->max < freq)
+        if (policy->max < cpu_set_freq[cpu])
             ret = __cpufreq_driver_target(policy, policy->max,
                         CPUFREQ_RELATION_H);
-        else if (policy->min > freq)
+        else if (policy->min > cpu_set_freq[cpu])
             ret = __cpufreq_driver_target(policy, policy->min,
                         CPUFREQ_RELATION_L);
-        else if (usr_speed)
-            ret = __cpufreq_driver_target(policy, freq,
+        else
+            ret = __cpufreq_driver_target(policy, cpu_set_freq[cpu],
                         CPUFREQ_RELATION_L);
 
         break;
@@ -57,11 +61,34 @@ static int cpufreq_governor_userspace(struct cpufreq_policy *policy,
     return ret;
 }
 
+int write_userspace_scaling_setspeed(unsigned int cpu, unsigned int freq)
+{
+    struct cpufreq_policy *policy = cpufreq_cpu_policy[cpu];
+
+    if (!cpu_online(cpu) || !policy)
+        return -EINVAL;
+
+    cpu_set_freq[cpu] = freq;
+
+    if (freq < policy->min)
+        freq = policy->min;
+    if (freq > policy->max)
+        freq = policy->max;
+
+    return __cpufreq_driver_target(policy, freq, CPUFREQ_RELATION_L);
+}
+
 static void __init 
 cpufreq_userspace_handle_option(const char *name, const char *val)
 {
-    if (!strcmp(name, "speed") && val)
-        usr_speed = simple_strtoul(val, NULL, 0);
+    if (!strcmp(name, "speed") && val) {
+        unsigned int usr_cmdline_freq;
+        unsigned int cpu;
+
+        usr_cmdline_freq = simple_strtoul(val, NULL, 0);
+        for (cpu = 0; cpu < NR_CPUS; cpu++)
+            cpu_set_freq[cpu] = usr_cmdline_freq;
+    }
 }
 
 struct cpufreq_governor cpufreq_gov_userspace = {